Cotton picking spindle



July 5, 1960 GRAY EI'AL 2,943,431

COTTON PICKING SPINDLE Filed Feb. 3, 1959 2 Sheets-Sheet 1 July 5, 1960 Filed Feb. 3, 1959 J. H. GRAY ETAI- COTTON PICKING SPINDLE 2 Sheets-Sheet 2 JWLBP @Xhwqm I. wand Unite Stats Patent Ofifi'ce 2,943,431 Patented July 5, 1960 signors to Allis-Chalmers Manufacturing Company, Milwaukee, Wis.

Filed Feb. 3, 1959, Ser. No.'790;859

7 Claims, (CI. 56-50) The invention relates to cotton picking spindles, and it is concerned more particularly with an improved spindle for cotton harvesting machines of the type wherein a stationary stripper assembly rather than a rotary dofiing mechanism is used for removing the cotton from the spindles.

Cotton harvesting machines of the stationary stripper type are commonly equipped with spindles in the form of cylindrical rods, and numerous attempts have been made during the past to improve this type of spindle.

Aggressiveness, that is the ability of the spindle to grab the cotton iibers, presents a problem because burrs, sticks, dry leaves and other 'tras'h usually present around the ripe bolls should "be kept out of the harvested cotton. If the spindle is too aggressive, the collected amount of foreign matter will be objectionable and reduce the grade of the cotton.

Another problem is wear of the spindles and of the stripper. The spindles should be stripped clean and for that purpose radial play of the spindles within the stripping gaps must be kept at a minimum. Frequent readjustments of :the stripping gaps to compensate for wear are obviously objectionable. The edges of the stripper plates at the entrance side of the gap should be sharp and if they become rounded by wear some of the cotton will be drawn into the gap and adhereto the spindle. On the other hand, wear of the spindles themselves is apt to reduce their aggressiveness by drilling points, edges or other surface irregularities which may be provided to cause winding of the cotton upon the spindles.

Another problem is resistance of the spindle against stripping which may be caused by the mentioned points,

edges or other surface irregularities. If the resistance is too high :the powerrequirements, loads and stresses will be excessive, and if the stripping resistance is too low the-cotton is apt to be flung off'the spindles by centrifugal force when they whip around the slat beltsprockets. .Particularly if the spindles are provided with sharp sawlike teeth, .as has been proposed, impact of the teeth upon the stripper plates may have .at least three damaging results. First, the teeth .may be rapidly dulled; second, the stripper plates .may be worn excessively; .and :third, the teeth may be :bent over or curled like hooks, making stripping :exceedingly'diflicult. When a spindle with such curled points enters an open cotton boll, the :fibers will slide over the points and will not be grabbed by it as they would beif the points were sharp.

Still another problem is production costs. The well known fluted type spindle, which is shown for instance in US. Patent 2,671,298 issued on March 9, 1954, to R. C. Fergason, can be produced at relatively low costs by a knurling process, but other types especially those having barbs or teeth present a cost problem.

Generally, it is an object of the invention to provide an improved cotton picking spindle of the cylindrical rod type which overcomes all of the hereinabove "outlined difiiculties in -a practical and entirely satisfactory manner. More specifically, it is an object of the invention to provide an improved cotton picking spindle of the .cylindrical rod type having picking teeth arranged and shaped in such a manner that the spindle not only affords the desired degree of aggressiveness and long lasting wearing qualities, but that it also lends itself to manufacture at relatively low cost with ordinary milling cutters.

Another object of the invention is to provide an improved cotton picking spindle of the hereinabove outlined character from which the cotton can be stripped axially Without undue resistance and without tearing of the cotton fibers.

These and other objects and advantages are attained by the present invention various novel features of which will be apparent from the description herein and the accompanying drawing disclosing an embodiment of the invention, and will be more particularly pointed out in the appended claims.

In the drawing:

Fig. 1 is a diagrammatic top view with parts broken away and shown in section of a cotton picking mechanism incorporating rod type picking spindles;

Fig. 2 is an enlarged side view with parts broken away 'iIJnd shown in section of one of the spindles shown in Fig. 3 is a side view similar to Fig. 2 but taken at right angles to the direction in which the view of Fig. 2 is taken;

Fig. '4 is a greatly enlarged view of part of the spindle shown in Fig. 2, the view of Fig. 4 likethe view of Fig. 2 showing the spindle rotated about its axis to a position in which the plane of the continuous axial groove surface extends parallel to the plane of the paper;

Fig. 5 is a section on line V-V of Fig. 4;

Fig. 6 is an enlarged detail view of part of Fig. 2, the View of Fig. 6 showing the spindle rotated about its axis to a'position in which the bottom edges of the notches extend parallel to the plane of the paper;

Fig. 6A is an end view of Fig. 6;'

Fig. 6B is a side view of Fig. 6 taken in the direction of arrow VI;

Fig. 7 is a perspectiv, enlarged three-quarter front view of the spindle portion shown in Figs. 6-, 6A, and 6B, the view of Fig. 7 being taken from the trailing side of the spindle;

Fig. 8 is a perspective, enlarged three-quarter front view of the spindle portion shown in Figs. 6, 6A and 6B, the view of Fig. 8 being taken from the leading side of the spindle;

Fig. 9 is a perspective, enlarged three-quarter front view of an axially grooved cylindrical rod portion illustrating a step in the manufacture of the spindle shown in Figs. 2 and 3;

Fig. 10 is a schematic View illustrating a simultaneous grooving operation on a number of cylindrical. spindle rods;

Fig. 11 is a schematic view illustrating a simultaneous nc ching operation on a number of grooved cylindrical spindle rods; and

Fig. 12 is an end view of the parts shown in Fig. 11, the view of Fig. 12 being taken from the left end of Fig. ll.

The picking mechanism shown in Fig. l conforms vgenerally with well known principles of construction and operation. It is shown in working relation to a row of unpicked cotton plants 1 at the left end of the figure and some picked cotton plants ,2 at the right .end. A pair of dividers 3 and 4 which straddle the unpicked \cotton plants 1 are mounted on a framework generally designated by the reference character 6. The dividers ,convergerearwardly toward each other, and when the machine advances in the direction of arrow v7 they crowd the cotton plants into the picking tunnel 8 of the machine. Within the tunnel 8 removal of the cotton lint from open bolls is effected by means of picking spindles 9.

In Fig. 1, an endless series of seventy-eight picking spindles 9 are shown arranged in an oblong loop around a rear drive sprocket 11 and a front idler 12. The spindles 9 are of the cylindrical rod type and incorporate features of the present invention which will be explained more fully hereinbelow. In conformity with conventional practice the spindles are mounted on an articulated slat belt 13, and in actual practice several endless series of spindles like the series shown in Fig. 1 are carried by the slat belt 13 in vertically spaced, horizontal planes, respectively.

At the upper part of Fig. l a stripping mechanism of conventional construction is generally designated by the reference character 14. It includes an assembly of stationary, vertically spaced stripper bars 16 which provide a vertical series of horizontal stripping gaps, one for each endless seriees of spindles 9.

The arrow 17 in Fig. 1 indicates the direction in which the sprocket wheel 11 is driven in operation of the machine. Each of the spindles 9 has a drive roller 18 (Figs. 2 and 3), and when the slat belt 13 is driven by the sprocket wheel 11 the rollers 18 roll on hori zontal rubber faced tracks, not shown, which are fixedly mounted on the frame 6 in proximity to the picking tunnel 8. The horizontal spindle drive tracks have forward ends in proximity to the idler 12 and terminate at their rear ends in proximity to the drive sprocket 11. Upon movement of the slat belt 13 by rotation of the drive sprocket 11 the spindles 9 start rotating on their axes when their rollers 18 hit the forward ends of the drive tracks and the spindles continue to rotate throughout their rearward movement along the drive tracks. Rotation of the spindles ceases when their rollers run off the rear ends of the drive tracks, and thereafter the spindles are carried around the rear drive sprocket 11, through the stripping mechanism 14 and around the front idler 12 without rotating on their axes.

At the entrance end of the picking tunnel 8 the free end 19 of one of the picking spindles is shown in a position of initial contact with an open cotton boll. As the ma chine advances, the free spindle end 19 follows an arcuate path of movement across the Width of the picking tunnel until it reaches a point of maximum penetration into the laterally constricted cotton plant as indicated by the reference character 21. Cotton fibers which are grasped by the free end 19 of a rotating spindle will therefore be wound spirally upon the spindle during backward movement of the latter into the picking tunnel. In Fig. l, the spiral formation of the cotton tufts is schematically indicated on some of the spindles in the picking tunnel and also at the entrance side of the stripping mechanism 14. As the spindles pass through the gaps between the stripper bars 16, axial push is exerted upon the coiled cotton tufts so that the tufts will ultimately slide off the free ends of the spindles. The coiling of the cotton on the spindles and the axial thrust upon the coiled tufts incidental to the stripping operation are of particular significance in connection with the herein disclosed improved type of spindles, as will become more fully apparent from the explanations hereinbelow.

In picking mechanisms which are generally constructed as outlined in Fig. 1 but which are equipped with conventional rod type picking spindles provisions have heretofore been made for moistening the spindles preparatory to their entry into the picking tunnel. In Fig. 1 the usual spindle moistening apparatus has been omitted because the herein disclosed improved spindles are capable of etficiently picking cotton while they are dry.

Referring to Figs. 2 and 3, the part of the spindle 9 which extends from its right end to the left for about one-half of the spindle length forms the rear part of the spindle and is of conventional construction. It ineludes axially aligned cylindrical rod portions 22, 23 and 24, and the drive roller 18 which is press fitted upon the rod portion 23. The rod portions 22 and 24 are of the same diameter and present smooth cylindrical surfaces all around their peripheries, the portion 22 serving as a rear journal, and the rearward part of the portion 24 adjacent the roller 18 serving as a forward journal. The intermediate rod portion 23 is slightly enlarged radially by knurling so that it will lock in a bore of the roller 18 which is large enough to slide over the journal 22 without marring its surface.

The picking portion of the spindle extends rearwardly from the free forward end of the spindle, that is, from left to right in Figs. 2 and 3, and is constructed as follows. Referring to Figs. 4 and 5, a cylindrically arcuate surface 26 of the same radius as the journal portions 22 and 24 extends axially of the spindle and forms the major part of the periphery of the picking portion. The reference character 27 in Figs. 5, 6A and 9 designates a single axially extending dihedral groove in the picking portion of the spindle. The picking portion has a continuous plane surface 28 which forms one wall of the groove 27 and which intersects the cylindrically arcuate spindle surface 26 along a straight edge 29. The other wall of the groove 27 is designated in Fig. 5 by the reference character 31, and a series of picking teeth 33 (Figs. 2 and 3) define successive dihedral notches 32 in the picking portion of the spindle along the other wall 31 of the groove 27, one notch 32 between each pair of successive teeth 33. Each tooth 33 has a straight axial edge portion 34 (Fig. 4) of predetermined length at the intersection of the groove wall 31 with the cylindrically arcuate surface 26.

The dihedral angle a of the groove 27 is less than V ninety degrees, as shown in Fig. 5. The preferred size of this angle is about seventy-three degrees.

The configuration of the dihedral notches 32 and the angularity of their walls relative to each other and relative to the spindle axis are illustrated by Figs. 3 through 8. Referring first to Fig. 3, each notch 32 intersects the groove wall 31 on converging edges 36 and 37, the edge 36 forming a tooth front edge, and the edge 37 forming a tooth rear edge. The plane of the surface 28 extends in Fig. 3 at right angles to the plane of the paper, and the plane of the groove wall 31 which contains the tooth front and rear edges 36, 37 is inclined from the plane of the paper toward the observer because the dihedral groove angle a is less than ninety degrees, as shown in Fig. 5.

The arrow 38 in Fig. 3 indicates the direction in which the spindle is rotated in operation. Accordingly, the tooth faces which coincide with the plane of the groove wall 31 will be termed the leading faces of the teeth. They are designated in Fig. 8 by the reference character 39 and each is bounded by the tooth front edge 36, the peripheral, axially extending or radially outer tooth edge 34, the tooth rear edge 37 and by a bottom edge along the intersection of the dihedral groove walls 28 and 31 with each other and which is indicated in Fig. 4 by the dotted line 47. The leading tooth faces 39 are under cut, that is, their radially outer edges 34 overhang their bottom edges 47.

Referring to Fig. 7, a rearward wall of each of the dihedral notches 32 defines a tooth front face 41., and a forward wall of each of the dihedral notches defines a tooth rear face 42. Each tooth front face 41 is bounded by a tooth front edge 36, an elliptically arcuate edge 43 on which the cylindrically arcuate spindle surface 26 is intersected by the rear wall of the adjacent dihedral notch 32, and by the bottom edge 44 of the adjacent dihedral notch 32. The tooth front faces 4}. are undercut, that is, their radially outer edges 43 overhang their bottom edges 44, as indicated in Figs. 3, 4, 7 and 8.

Each tooth rear face 42, as shown in Fig. 7, is bounded by a tooth rear edge 37, an elliptically arcuate edge 4-6 on which the cylindrically arcuate spindle surface 26 is intersected by the front wall of the adjacent dihedral notch 32, and by the bottom edge 44 of the adjacent dihedral notch 32.

The bottom edges 44 of the dihedral notches 32 are angled relative to the spindle axis so as to extend obliquely rearward from their intersection points 47 (Figs. 4 and 5) with the groove wall 31. From Figs. 4 and 5 it will further be noted that the bottom edges 44 of the notches 32 are angled relative to the surface 28 so that the plane of the latter, which is indicated in Fig. 5 by the dash-dotted line 48, overlies the points 49 at which the notch bottom edges 44 intersect the cylindrically arcuate spindle surface 26. p

In Fig. 6, the picking portion of the spindle as shown extends arallel to the plane of the pa er as it does in Figs. 2, 3 and -4. However, as distinguished from the 'views of Figs. 2, 3 and 4, the view of Fig. 6 shows the spindle rotated about its axis to a position in which the plane of the tooth front face 41 extends at right angles to the plane of the paper. The angularity of the notch bottom edge 44 relative to the plane 48 of the flat 28 as shown in 5 is such that rotation of the spindle about its axis to the position shown in Fig. 6 brings the notch bottom edges 44 into parallelism with the plane of the paper.

Fig. "6B is a View of the spindle portion of Fig. 6 looking in the direction of the notch bottom edge 44. This view shows the true dihedral angle B of one of the notches 32. Like the dihedral groove angle a the dihedral notch angle 18 is preferably about seve'nty three degrees.

The free end of each of the spindles is chamfered as best shown at 51 in the enlarged view of Fig. 4.

From the foregoin it will be noted that the herein disclosed cotton picking spindle is of the cylindrical rod type and comprises an elongated body, a picking portion at one end 'of said body, and a single longitudinal "series of picking teeth 33 on said picking portion. Each of the picking teeth has a top surface which is continuous with and forms'part of the cylindrically arcuate peripheral surface of the picking portion. 111 the embodiment of the invention as 'i'llustrat'ed by Fig. 4, such tooth top surface is b'ounded'by the edges 34, 43 and 46. Each of the picking teeth further has three flat faces which extend inwardly from the tooth top surface and respectively present a tooth front face shown at 41 in Fig. 7, atooth rear face shown at 42 in Fig. 7, and a tooth side face shown at 3 9 -in Fig. 8. The respective side faces 39 of the picking teeth 33 lie in a common plane which extends longitudinally of the spindle, such plane being indicated in Fig. 5 by the reference character 3 1. The tooth front and rear faces 41, 42 are inclined relative to each other so as to form dihedral notches 32' between pairs of teeth 33, and a straight axial edge portion 34 of predetermined length on each of said teeth along the intersection of the common plane 31 with the cylindrically arcuate peripheral surface 26 of the picking portion. The picking portion of the spindle also has a longitudinally extending, recessed plane surface, as represented by the fiat surface 28, which extends from the tooth side faces 39 to the cylindrically arcuate peripheral surface 26 of the picking portion.

The tooth front faces 41' are angled relative to the axis of the cylindrically arcuate peripheral surface 26 in undercutting relation to their respective teeth as explained hereinbefore in connection with 'Fig. 4, and the toothirontand rear faces 41, 42 are further angled relative to said axis so that the lines 44 (Fig. 4) on which said tooth front and rear faces intersect each other at the apexe's of the dihedral notches 32, respectively, extend obliquely rearward from their oints of intersection 27 (Fig. 5) with the commonplane of the tooth side faces 39.

The operation of a picking mechanism as shown in Fig. 1 and equipped with spindles of the herein disclosed construction is as follows. Upon contact of the free ends of rotating spindles with the fibers of open cotton bolls at the entrance end of the picking tunnel spiral wrapping of cotton about the spindles will begin. At the intersection of the edges 34, 36 and 43 each tooth presents a relatively sharp point on which loose cotton fibers will get caught and become attached to the spindle. However, the point afforded by the intersecting tooth edges is not a needle point which may dull easily or bend over, nor is it excessively aggressive so that it would pick an undesirable amount of trash such as grass, leaves or sticks. As the rotating spindles continue to advance into the picking tunnel they will penetrate deeper into the constricted cotton plant and pick up more cotton. While the cotton is Wrapped around the spindles it will become packed in the notches 32, but it will also be coiled spirally about the spindles as has been mentioned hereinb'efore. When the mass of spirally coiled cotton encounters the stationary bars 16 of the stripping mechanism, axial compression of the coils causes them to increase their diameter. Such diametrical increase of the coils eases the pressure which 'holds :the cotton in the notches 32, and stripping of the spindle is thus facilitated. It should be noted that the notches are only on one side of the spindle and that most of the spindle periphery is smooth along the cylindrically arcuate surface 26. The radial expansion of the coiled cotton due to axial compression at the stripper is only slight, but since the notches are only at one side of the spindle it is sufiicient to avoid tearing of the cotton during its movement over the forwardly inclined tooth rear faces 42 toward the free ends of the spindles. On the other hand, packing of the cotton within the notches 32 during the picking operation will prevent the cotton from being flung off the spindles when they whip around the slat belt drive sprocket 11.

The presence of the axially extended radially outer tooth edges 34 facilitates movernent of the spindles through the stripping gaps so that wear of the spindles as well as of the stripper shoes will be kept at a minimum. If wear of the spindles does occur the aggressiveness of the spindle is not materially impaired by any dulling of the front and side edges of the picking teeth.

Another important advantage of the herein disclosed spindle is that it can be manufactured economically by mass production methods. .A series of steps for a preferred method of manufacturing the spindle are illustrated by Figs. .9, 1'0, 11 and 12.

Fig. 9 shows a portion of a spindle blank 52 which has been initially machined to provide the dihedral groove 27. The blank is preferably cut from round wire ;or bar stock having the finished spindle diameter and :the length of the blank is that of the finished spindle. The chamfer 51 (Fig. 4) may be formed by the same cutter which severs the stock. Prior to the cutting of the groove 27, the knurls of portion 23 may be rolled .into the :blank.

Fig. 10 illustrates diagrammatically the simultaneous grooving of three spindle blanks. Three conical mill- .ing cutters 53 are aligned on a horizontal arbor 54, and the spindle blanks 52 are held in a fixture, not shown, below the cutters so as to extend side by side at right angles to the axis of the arbor 54. Each cutter 53 has a base angle-a which is the same as the dihedral groove angle on of the spindle. Feeding the assembly of blanks '52 horizontally at right angles to the axis of the arbor so that the cutters will mill into the spindle blanks from one end thereof and parallel to the spindle axes will form the dihedral groove of desired length on each blank. The fiat 28 (Fig. 5) of the groove is preferably formed by circumferential sonically inclined cutting edges of the cutters 53,' and the groove wall 31 is preferably formed by axially projecting cutting edges at the base end of each cutter. For mass production purposes any desired number of spindle blanks may be simultaneously grooved in the manner illustrated by Fig. 10.

The herein disclosed spindle may be termed a lefthand spindle because, in order to pick, it must be rotated anticlockwise as viewed from the rear of the drive roller. In a picking mechanism of the type shown in Fig. l, lefthand and righthand spindles are usually employed together. That is, an entire series of spindles such as shown in Fig. 1 are lefthand spindles, and righthand spindles are used for the next vertically adjacent spindle series. In other words, the slat belt 13 carries vertically alternate series of right and lefthand spindles.

The righthand spindles are opposite hand duplicates of the herein disclosed lefthand spindle. The grooving operation illustrated by Fig. can be performed so as to cut the grooves for lefthand spindles into one set of spindle blanks which are held in one section of a fixture, not shown, and so as to cut the grooves for righthand spindles into another set of spindle blanks which are held in another section of the same fixture. The spindle blanks of one set would in that case be axially aligned with the spindle blanks of the other set, and in order to mill the sets one is fed toward the cutter assembly with the spindle ends next to the other set first, and the other set is fed toward the cutter assembly with the spindle ends next to said one set first. While one set is being milled the other set which has been milled may be replaced by a new set of spindle blanks.

Figs. 11 and 12 illustrate diagrammatically the simultaneous notching of three grooved spindle blanks 52. A number of conical milling cutters 56 corresponding to the number of notches are aligned on an arbor 57. For purposes of simplification, only three milling cutters 56 are shown in Figs. 11 and 12. If the finished spindle is to have ten notches 32, like the one shown in Figs. 2 and 3, the arbor 57 will have ten conical milling cutters like the ones shown at 56 in Figs. 11 and 12. The grooved spindle blanks 52 as shown in Figs. 11 and 12 extend horizontally side by side below the cutter assembly and they are retained in a fixture, not shown, which places the spindle blanks into an oblique relation to the base planes of the cutters 56 which are indicated in Fig. 11 by the dash-dotted lines 58. The axis of each spindle blank 52 in Fig. 11 intersects the base planes 58 of the cutters 56 at an angle 7 which is the same as the angle 7 shown in Fig. 6 and which represents the angle at which the plane of the tooth front face 41 intersects the spindle axis.

As further shown in Fig. 11, the position of the spindle blanks 52 relative to the cutters 56 is such that the forward ends of the spindle blanks which correspond to the free or forward ends of the finished spindles are located at the same side of the cutter base planes 58 as the tapered ends of the cutters.

The position of the spindle blanks 52 relative to the cutters 56 in Figs. 11 and 12 is further such that the surface 28 of each spindle blank is tilted at an angle 6 (Fig. 12) downwardly from a horizontal plane through the groove apex line 47 (Fig. 4). The tilt angle 6 shown in Fig. 12 is the same as the angle 6 shown in Fig. 5, and this angle determines the amount of undercut of the tooth front face 41. Stops 60, one for each grooved spindle blank are provided on the fixture, not shown, which retains the spindle blanks in their proper positions relative to the cutters 56. Rotation of the spindle blanks on their axes until the groove walls 31 engage the stops 60 places the surfaces 28 at the desired angles 6.

Horizontal movement of the obliquely disposed and rotationally adjusted spindle blanks 52 at right angles to the axis of arbor 57 toward the right in Fig. 11 feeds the spindles to the cutters 56 so that the desired number of notches 32 will be milled at one pass into a set of spindle blanks. For purposes of simplification, only three grooved spindle blanks 52 have been shown in Figs. 11 and 12, but obviously any desired number of grooved spindle blanks may be notched in the manner illustrated by Figs. 11 and 12. As shown in Fig. 11, the spindle blanks are staggered so that their forward ends terminate in a common vertical plane at right angles to the axis of arbor 57.

The taper of each of the cutters 56 as indicated by the angle 5 in Fig. 11 is the same as the dihedral notch angle 5 shown in Fig. 6B. Variation of the tilt angle 6 in Fig. 12 will vary the amount of undercut of the tooth front face 41. Reduction of the tilt angle to zero would obviously place the tooth front face into right angle relation to the plane of the surface 28 which means that the tooth front face would have no undercut. On the other hand, increase of the tilt angle beyond the size of the angle 6 shown in Fig. 12 would proportionally increase the amount of undercut of the tooth front face 41.

Figs. 11 and 12 illustrate the simultaneous notching of a set of lefthand spindles. The principles of the herein disclosed method of notching the spindles may be used analogously for notching righthand spindles. For instance, grooved righthand spindle blanks could be positioned relative to the cutter assembly 56 so as to extend in the direction of dash-dotted line 52' and intersect the cutter base planes 53 at angle 7 at the right of the arbor 57. The free ends of the grooved righthand spindle blanks would in that case again be located at the same side of the cutter base planes 58 as the tapered ends of the cutters, and the blanks would be tilted about their axes so that their flats 28 extend downwardly at angle 6 from a horizontal plane through the groove apex lines 47. Feeding of the righthand spindle blank assembly from the left to the right of Fig. 11 into the cutter assembly 56 would then cause the milling of notches 32 into righthand spindle blanks.

Generally, the herein disclosed method of making either righthand or lefthand cotton picking spindles comprises the steps of positioning a cylindrical spindle blank in radially spaced right angle relation to the axis of a milling cutter, as illustrated by Fig. 10; relatively moving said blank and cutter axially of said blank and thereby forming an axially extending dihedral groove in the blank; positioning the blank relative to a conical milling cutter so that the axes of the blank and last mentioned cutter extend in relatively spaced parallel planes, respectively, and in acute angle relation to each other, as illustrated by Figs. 11 and 12; and relatively moving the blank and last mentioned cutter at right angles to the axis of the last mentioned cutter and parallel to said planes to thereby form a dihedral notch in said blank in intersecting relation to said groove.

The step of notching the spindle blank preferably involves the formation of a number of notches by means of a unitary assembly of axially aligned conical milling cutters as illustrated by Figs. 11 and 1 Another step of the herein disclosed method is the tilting of the spindle blank about its axis to a notch cutting position as illustrated by Fig. 12, in which the path of cut of the conical cutter assembly extends through one wall of the dihedral groove and the other wall of said groove diverges from said path of cut, as illustrated by the angle 6 in Fig. 12.

The preferred sequence of the recited steps is to form the groove before the notches are formed, but obviously the groove could be formed after the notches have been formed.

It should be understood that it is not intended to limit the invention to the exact forms and details herein described, and that the invention includes such other forms and modifications as are embraced by the scope of the appended claims.

What is claimed is:

1. A cotton picking spindle of the cylindrical rod type comprising an elongated body, a picking portion at one end of said body, and a single longitudinal series of picking teeth on said picking portion; each of said picking teeth having a top surface continuous with and forming part of a cylindrically arcuate peripheral surface of said picking portion, and three flat faces extending inwardly from said top surface and respectively presenting a tooth front face, a tooth rear face and a tooth side face; the respective side faces of said picking teeth lying in a common plane extending longitudinally of said spindle, and said tooth front and rear faces being inclined relative to each other so as to form dihedral notches between pairs of said teeth and a straight axial edge portion of predetermined length on each of said teeth along the intersection of said common plane with said cylindrically arcuate peripheral surface; said picking portion also having a longitudinally extending recessed plane surface extending from said tooth side faces to said cylindrically arcuate peripheral surface of said picking portion.

2. A cotton picking spindle as set forth in claim 1 wherein said longitudinally extending recessed plane surface of said picking portion extends from said side faces of said picking teeth at an angle of less than ninety degrees.

3. A cotton picking spindle as set forth in claim 1 wherein the dihedral angle of each of said notches is less than ninety degrees.

4. A cotton picking spindle as set forth in claim 3, wherein said tooth front faces are angled relative to the spindle axis in undercutting relation to their respective teeth.

5. A cotton picking spindle of the cylindrical rod type comprising an elongated body, a picking portion at one end of said body, and a single longitudinal series of picking teeth on said picking portion; each of said picking teeth having a top surface continuous with and forming part of a cylindrically arcuate peripheral surface of said picking portion, and three flat surfaces extending inwardly from said top surface and respectively presenting an undercut tooth front face, a tooth rear face and a tooth side face; the respective side faces of said picking teeth lying in a common plane extending longitudinally of said spindle, and said tooth front and rear faces being inclined relative to each other at an angle of less than ninety degrees so as to form dihedral grooves between pairs of said teeth and a straight axial edge portion of predetermined length on each of said teeth along the intersection of said common plane with said cylindrically arcuate peripheral surface; and said picking portion also having a longitudinally extending recessed plane surface extending at an angle of less than ninety degrees from said tooth side faces to said cylindrically arcuate peripheral surface of said picking portion.

6. A cotton picking spindle as set forth in claim 5 wherein said tooth front and rear faces are angled relative to the axis of said cylindrically arcuate peripheral surface so that the lines on which said tooth front and rear faces intersect each other at the apexes of said dihedral notches, respectively, extend obliquely rearward from their points of intersection with said common plane.

7. A cotton picking spindle as set forth in claim 6 wherein said lines on which said tooth front and rear tooth faces intersect each other are angled relative to said recessed plane surface so that the plane of the latter will overlie the points at which said lines intersect said cylindrically arcuate peripheral surface portion.

References Cited in the file of this patent UNITED STATES PATENTS 345,312 Mason July 13, 1886 369,851 Haselton Sept. 13, 1887 388,797 Todd Aug. 28, 1888 423,540 Todd Mar. 18, 1890 439,794 Todd Nov. 4, 1890 685,439 Campbell Oct. 29, 1901 908,638 Appleby Jan. 5, 1909 1,008,230 White Nov. 7, 1911 2,546,185 Hagen Mar. 27, 1951 2,787,109 Lindsay Apr. 2, 1957 

